EFFECT OF PATTERNS OF AVERSIVE AND APPETITIVE CONDITIONED STIMULI ON INCIDENCE OF GASTRIC LESIONS IN IMMOBILIZED RAT

Studied changes in the frequency of gastric lesions in 120 ulcer-susceptible female albino rats under restraint as a function of presentations of a light stimulus and a buzzer previously associated with feeding and electric shock, respectively. At 11/2-min intervals during 24 hr. of restraint, different groups received the 2 CSs simultaneously, the 2 CSs consecutively, or 1 of the stimuli separately. Gastric lesions were found to be exacerbated by simultaneous presentation of the 2 CSs (p < .001) and ameliorated by the CS for feeding and absence of shock (p < .001). Results supported the hypothesis that conflict phenomena are generated when a stimulus pattern tends to elicit incompatible responses, but no 1 response is able to achieve dominance. (PsycINFO Database Record (c) 2006 APA, all rights reserved). © 1969 American Psychological Association.